An existing terminal device is already not limited to a touchscreen on a single side. There are already some terminal devices on the market that are provided with back touchscreens in addition to front touchscreens and support control of the terminals by the back touchscreens to facilitate user operation. In the prior art, to avoid a user misoperation, a back touch event reported by a back touchscreen is a predefined particular event, or a back touchscreen exclusively uses independent touch coordinate information different from that of a front touchscreen. The back touchscreen and the front touchscreen are touch input devices that are independent from each other, and the back touchscreen independently reports a touch event, to implement control of software.
However, for third-party application software developed for an ordinary mobile phone form having a single touchscreen, because the third-party application software can respond only to a system default touch event and cannot identify a particular event reported by a back touchscreen, the third-party application software cannot respond to an event reported by the back touchscreen. Therefore, a case like this may occur: when a terminal user runs some third-party application software developed for an ordinary mobile phone form having a single touchscreen, a back touchscreen cannot achieve effective control.